The present invention relates generally to teaching aids for the game of tennis, and, more particularly, to teaching aids for developing player skill in striking a tennis ball with a tennis racket in such a manner that the ball is contacted by a desired particular portion of the stringed area of the racket.
As is well known to players and teachers of the game of tennis, a tennis racket has a particular, relatively small portion of its stringed area which provides a maximum response when the tennis ball is struck by this portion. This high-response area of the strings is widely known as the "sweet spot" of the racket, and consistently striking the ball with this area gives the player better control of the ball, and allows the ball to be driven from the racket with a significantly higher velocity than would otherwise be obtainable. The sweet spot of the racket is not in exactly the geometric center of the stringed area of the racket, but is located slightly off-center, closer to the handle of the racket.
As is also well known to players and teachers of tennis, contacting the ball with any portion of the racket other than the sweet spot can produce severe twisting and other stresses on the racket, and these are transmitted to the arm of the player. Hitting the ball consistently with the sweet area reduces these stresses, and thereby reduces any likelihood of "tennis elbow" and other common complaints of amateur tennis players.
Various techniques have been tried over the years to provide players with a simple and convenient indication as to whether they were contacting the sweet spot of the racket. One technique for indicating that the sweet spot has been contacted involves the use of sensors of various kinds attached to the racket strings and wired to a sound-producing device to provide an audible indication when the ball strikes the sweet spot.
Another device utilizes a small square or rectangular sheet of material secured to the stringed area by bolts and washers, and spaced above the strings by spacers. The sheet of material is intended to give out a distinctive sound when struck by a tennis ball in its center. However, it can work only for one side of the tennis racket, therefore precluding its use for backhand shots. Moreover, since the sheet is raised a substantial distance above the strings of the racket, the ball will be significantly deflected from its intended path if the edge of the device is struck.
It will be appreciated from the foregoing that there is still a definite need for a simple and inexpensive teaching aid which will provide a positive indication to the player whenever the sweet spot of the racket contacts the tennis ball. The present invention fulfills this need.